The present invention relates generally to gearshift mechanisms for use in manual transmissions and, more particularly, to a shift inhibitor apparatus that is integrated into the shifter assembly for preventing a vehicle operator from shifting into the reverse gear position in certain circumstances.
As is known, conventional manual transmissions are typically equipped with a shifter assembly for permitting a vehicle operator to selectively shift between various forward ratio gears and a reverse gear. The shifter assembly includes a tower housing secured to an exterior surface of the transmission casing and a shift lever that is operably coupled to a gearshift mechanism located within the transmission casing. Typically, the gearshift mechanism has a standardized shift pattern such that the shift lever is linearly movable along a "Neutral" path to a plurality of preselected "gate" position, each of which defining a shift plane for a pair of the ratio gears. Most commonly, a gate position located at one end of the Neutral path defines the shift plane between the highest forward ratio gear position (i.e., 5th gear) and the reverse gear position. To prevent the vehicle operator from inadvertently down-shifting along this shift plane from the highest forward gear position into the reverse gear position, it is known to "block" such a shift by installing a shift inhibitor device in conjunction with the gearshift mechanism.
One example of a shift inhibitor device of the type installed within the manual transmission and in relatively close proximity to the gearshift mechanism is shown in U.S. Pat. No. 4,738,153 to Sabel. Alternatively, it is known to mount a shift inhibitor device to an exterior surface of the transmission casing, such arrangements being shown in U.S. Pat. No. 4,638,678 to Gorman and U.S. Pat. No. 5,101,680 to Parsons. However, each of the afore-noted shift inhibitors can not be readily installed on existing or otherwise standard manual transmissions without requiring costly redesign and rework.
While conventional shift inhibitors perform satisfactorily, the need exists to develop a shift inhibitor that can be easily adapted for application to virtually any existing high-volume manual transmission.